1. Field of the Invention
The present invention relates to a method of producing a ceramic-metal composite body, and more specifically, a turbine rotor.
2. Related Art Statement
Since ceramics such as zirconia, silicon nitride and silicon carbide are excellent in mechanical strength, heat resistance and wear resistance, they have attracted attention as high temperature structural materials and wear resistive materials for gas turbine engine parts, engine parts and so on. However, the ceramics are inferior to the metallic materials in terms of shape formability because they are hard and brittle. Further, ceramics have weak resistance against impact forces due to their poor toughness. For this reason, it is difficult to form mechanical parts such as the engine parts only from the ceramic materials, and they are generally used in a composite structural body in which a metallic member is bonded to a ceramic member.
Heretofore, turbine rotors have been known as metal-ceramic composite bodies of this kind. FIG. 6 is a partial sectional view showing an example of such a turbine rotor. In FIG. 6, the turbine rotor is integrally formed by fitting a ceramic shaft 52 integrally formed with a turbine vane wheel 51 made of ceramics into a depression 54 of a metallic member 53. The fitting is ordinarily carried out through press fitting, shrink fitting, or expansion fitting. A fitting shaft 55 for mounting a compressor wheel not shown is provided on an opposite side to the turbine vane wheel side of the metallic member 53.